In conventional emergency evacuation slides, such as inflatable slides deployed from aircraft for an emergency evacuation, it is generally known that the energy released while a person slides down the slide is dissipated, i.e. converted to heat, by the friction between the clothing or skin of the person and the sliding surface of the emergency slide. Namely, the gravitational potential energy of a person sliding from a higher level to a lower level is converted to kinetic energy, and is then ultimately converted to and dissipated as heat due to the frictional contact of the person on the sliding surface. As a result, the sliding surface and the clothing and skin of the evacuating persons can become quite hot, whereby the degree of heating is ultimately dependent on the height difference that is spanned by the emergency slide. Also, sufficient friction must be provided so that the evacuating persons are discharged from the bottom end of the slide at acceptably low speeds for avoiding injuries.
It has been found in practice that the temperature levels reached during the use of conventional slides for single-deck aircraft are just barely within an acceptable range. However, in the next generation of high capacity aircraft and especially multi-deck aircraft, it will be necessary to provide emergency slides that can safely span substantially greater height differences between the upper deck of the aircraft and the ground. First of all, the emergency slides must be made substantially longer to span the greater height differences while still maintaining a slide angle within an acceptable range. More importantly, if the conventional slides with conventional sliding surfaces are simply made longer, then the thermally dissipated energy would heat the clothing and skin of the evacuated persons to such a high temperature that the persons could suffer burns.
Evacuation slides are also known, having deceleration means such as bumps, ridges, grooves or a high friction surface treatment on the sliding surface, for example as disclosed in U.S. Pat. No. 4,246,980 (Miller). Such slide surfaces dissipate the kinetic energy of the evacuating persons by frictional heating resulting from frictional sliding, as well as through the impact between the evacuating person and the ridges or ripples provided for the deceleration. If such slides are used for a greater height difference with a greater associated energy to be dissipated, the impact rubbing of the body of the evacuating person against the ridged surface can result in bruising as well as frictional skin burns to the person.